7:00 It waits two seconds to confirm that it is on solid ground and fires several pyros (small explosive devices) to cut the cables and a data umbilical cord. The powered descent stage then flies away and crash-lands approximately 450 meters away.
Within an hour or so we should have the first images from the surface, and by the end of the second month the onboard lab will have analyzed the first soil and rock samples. Don Foley
6:00 At approximately 20 meters above the Martian surface, the rover is lowered on three cables, a configuration known as the sky crane, and placed on the surface, with its wheels and suspension fully deployed. The rover touches down at approximately 0.75 meter a second. Don Foley
5:00 By this point, the rover is still supersonic. Designing the chute has been an especially challenging part of the mission. The physics of how a parachute inflates (or oscillates, or does not inflate) at these speeds is not well understood and is extremely difficult to model.
Shortly after deploying the parachute, the spacecraft jettisons its heat shield and turns on its ground-sensing radar system. At an altitude of about two kilometers, the spacecraft is traveling at about 100 meters a second—nearly the terminal velocity, the slowest that the atmosphere can brake an incoming spacecraft, which is still too fast for a safe landing. At this point, the rover drops out of the parachute, attached to a rocket-powered “backpack” that fires thrusters to control its descent. Don Foley
4:00 At an altitude of 10 kilometers, the spacecraft deploys a parachute that is 50 meters long and 21.5 meters in diameter. Don Foley
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3:00 The craft then flies horizontally, burning off speed, as side rocket thrusters steer it toward its landing site. Don Foley
2:00 The capsule ejects ballast (blocks of tungsten) to shift its center of mass and turn it into a wing that can be piloted. It encounters the upper Martian atmosphere at a hypersonic velocity of approximately six kilometers per second. A heat shield absorbs the tremendous energy of the resulting deceleration. Don Foley
1:00 Tucked inside an entry capsule, the rover first separates from its interplanetary propulsion and power systems. Don Foley
![From Space to Soil in 7 Minutes [Slide Show]](https://static.scientificamerican.com/sciam/cache/file/E40CE1AC-E4D4-4D97-BCA27B4C8EC1003B.jpg?w=590&h=393)
